Improvement in car-springs



G. DOUGLASS.

Carriage-Spring.

Patented May 26, 1863.

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AM. PHUTU-LITHO. CU. N.Y.( DSEORNES PRDCESS.)

NITED STATES PATENT OFFICE.

GEORGE DOUGLASS, OF SORANTON, PENNSYLVANIA.

IMPROVEMENT IN CAPI-SPRINGS.

Specication forming part'of Letters Patent No. 38,661, dated May 26, 1863.

.T 0 a/ZZ whom it may concern:

Be it known that I, GEORGE DoUGLAss, of Scranton, in the county of Luzerne and State of Pennsylvania, have invented a new and useful Improvement in Springs for Railroad- Oars and other Wheeled Vehicles; and I do hereby declare that the following is a full, clear, and exact description of the same, ret'- erence being had to the accompanying drawings, making a part of this specification, in which- Figure l is a side view of my invention; Fig. 2, a plan or top view of the same.

Similar letters of reference indicate corresponding parts in the two figures.

This invention consists in the employment or use of cast-iron seats in connection with a spring and end or connecting pieces, all arranged as hereinafter set forth, whereby it is believed that many advantages are obtained over the ordinary steel springs in common use.

'lo enable those skilled in the art to fully understand and construct my invention, I will proceed to describe it.

A A represent two cast-iron seats, which are of box form and provided at their ends with projecting lips a a, which are curved, and with the bottom of the seats conform to the shape of the central parts of the spring. The spring is a modification of the well-known elliptic spring, the ends ofthe inner leaves, b b, being bent in the form of loops or eyes a', and tted in metal end pieces, B, and secured therein by bolts c, which pass through washers d. The outer leaves, b b, are placed one over the other at the outer sides of the leaves b, and are secured in proper position by bolts e e, which pass through ears ff, at the opposite sides of the seats A, and through bars g, which extend across the inner surfaces ofthe leaves b. The projecting lips a a are curved a little outward from the outer leaves b, as shown clearly in Fig. l, so that the bearing or weight to which the spring is subjected will be at the center ofthe spring, as shown at hthat is to say, it will be at that point at rst,

but if the wei-ght is sufficient to compress the spring beyond a certain extent the ends of the lips a a will bear or press against the leaves b, and hence the spring will be strengthened in consequence of the weight or pressure being nearer the end pieces, B B, which connect the ends of the inner leaves, b b, together. This will be fully understood by referring to Fig.. 1, in which the ends of the lips a a are shown projecting out from the leaves b, in consequence of the spring not being compressed. Any number of leaves may be used as desired, and in case the invention be applied to carriage or wagon springs, where but two leaves, b b, would most generally be only required, it will be seen that another pair may be readily applied at any time, and in case of the breakage of the leaf a new one may be applied with the greatest facility; and if a leaf be broken at or near its center it will opl crate until anew one can be replaced. In fact, if all the leaves should be broken at their center the spring would operate perfectly so long as the end connections, B, remain firm.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

l. The employment or use, in connection with a steel spring, of seats A A, constructed and applied to the spring, substantially as and for the purpose herein set fort-h.

2. rlhe end pieces, B, provided with recesses to receive the eyes a at the ends ofthe leaves b b, in connection with the bolts e and washers d, all arranged substantially as herein set forth.

3. 'Ihe seats A A, provided with the lips a, a, and attached to the spring by means ofthe bolts e e and bars g, in combination with the end pieces, B B, having the ends of the leaves b secured in them by the bolts and washers, as described.

GEORGE DOUGLASS. Witnesses:

F. R. SHILs'roNE, JAMES HUGHES. 

